Internally Heated Steam Generation System and Heat Exchanger

ABSTRACT

A very high efficiency internally heated steam generation system and heat exchanger are disclosed, wherein a generally rectangular housing includes end and side walls and top and bottom walls, each containing a series of small-diameter interconnected serpentine tube coil sets. A heating chamber is located at the bottom portion and at the front of the container and includes a source of fuel to generate heat within the chamber. A source of water enters the container where it is heated and passes sequentially through the several coil sets where it is heated and changes phase into steam which then passes into one or more steam tanks where it is stored and extracted when needed for a variety of uses.

PCT FILING

This application claims priority under 35 U.S.C. 119(e) to U.S. Provisional Application No. 62/285,617, filed on Nov. 4, 2015, the contents of which are incorporated herein.

This is an International Application under the PCT

TECHNICAL FIELD

My invention is related to improvements in fuel-fired or electrically operated internally heated steam generation systems or heat exchangers which provide extremely high efficiencies. Steam produced by the internally heated steam generation system or heat exchanger of ray invention may be used for a variety of purposes including heating and electrical power generation to provide low cost utilities to factories, residential communities, office buildings, government installations, schools and the like.

BACKGROUND OF THE INVENTION AMD PRIOR ART

Condensing boilers or steam generation systems for the production of steam are very old in the prior art and many examples of the same appeared in the mid to late 1880's. Note by way of example the United States patents, LeBosqquet U.S. Pat. No. 190,054, Allen et al. U.S. Pat. No. 193,069, and Brooks U.S. Pat. No. 272,373. Since that time there have however been very few significant developments in this old art that have taken place in modern times. As will be apparent herein, my new design results in a significantly higher degree of thermal efficiency for such condensing boilers or heat exchangers and will provide cheaper and more efficient energy than solar or wind energy generation. This present invention also represents improvements in the invention described and claimed in my earlier U.S. Pat. No. 9,310,069 which issued on Apr. 12, 2016.

The two most common forms of alternative energy today are wind and solar systems which normally operate at between 20 to 35% efficiency.

My current design serves to generate steam using a series of serpentine wound coils that are embedded in refractory cement in order to increase thermal efficiency and heat recovery significantly greater than realized in the prior art.

The emitted steam may also be used to power a steam turbine the output of which can be coupled to a myriad of devices or systems.

OBJECTS OF THE INVENTION

Among the attributes and objects of my invention are the provision of a thermal storage system utilizing coils for steam production and/or heated water that capitalizes on thermal mass storage over extended periods of time, even after the source of fuel is removed, exhausted or is shut off.

It is a further object of my invention to achieve very high steam or water heating generation efficiency by means of heat transfer from the consumed fuel or electric power and the exhaust stream at a plurality of locations.

These, and other objects of my invention will be apparent from a reading of the following specification, drawings and claims.

SUMMARY OF THE INVENTION

The present invention comprises an internally heated steam generation system that relies upon thermal mass storage for the generation of steam or heated water which can be utilized for a variety of commercial and consumer purposes, including among others, the generation of electrical power, home and industrial heating of buildings and other structures.

The principal advantages of my new and improved steam generation system are:

optimizing energy efficiency;

reduction in the consumption of fuel or electric power resulting in extraction of maximum energy and to proportional reduction of pollutants and harmful waste products;

obtaining the maximum thermal flywheel effect;

due to the modular construction of my new system, the entire unit may be assembled in a factory thereby minimizing very expensive field erection and fabrication as is common with prior art structures and which ensures the high quality of the unit;

the ability to customize the unit for a variety of applications and locations;

the ability to provide a variety of applications, including the generation of electricity, the production of steam for industrial purposes, the production of hot water or steam for HVAC systems in commercial or residential structures for a wide variety of uses;

The ability to burn a wide variety of fuel sources, including, but not limited to natural gas, diesel oil, syngas, coal, propane, biofuels, and solid fuel materials such as, wood chips, animal carcasses, chopped wood, wood pellets, cardboard, etc. as well as electric power;

My new unit has been tested to run at 80% efficiency or better, depending upon the choice of fuel, resulting in use of less fuel and reduced carbon emissions.

Also incorporated herein is the use of tubes or coils that are embedded in a refractory cement and new steam generating coil configurations wherein parallel inlets and outlets are arranged and adjacent to each other and located within the same plane.

DESCRIPTION OF THE DRAWINGS

These and other objects of my invention will be appreciated and understood by those skilled in the art from the detailed description of the preferred embodiment of the invention and from the following drawings in which:

FIG. 1 is a front perspective view showing the installed internally heated steam generation unit and heat exchanger showing many of the internal components;

FIG. 2 is a front view of the invention;

FIG. 3 is a top elevation of the unit shown in FIG. 1;

FIG. 4 is a left side elevation of the unit;

FIG. 5 is a right side elevation of the unit.

FIG. 6 is an elevation of the rear of the unit;

FIG. 7 is a sectional view through the floor or bottom of the unit taken along line 7-7 of FIG. 4;

FIG. 8 is a sectional view through the mid-wall of the unit taken along line 8-8 of FIG. 4;

FIG. 9 is sectional view taken along the line 9-9 of FIG. 4;

FIG. 10 is a sectional view taken along the line 10-10 of FIG. 3;

FIG. 11 is a sectional view taken along the line 11-11 of FIG. 3; and

FIG. 12 is a sectional view taken along the line 12-12 of FIG. 4.

DISCLOSURE OF INVENTION AMD BEST MODE

With reference to the drawings, wherein like reference numbers in the views refer to the same elements of my construction in the several views, the condensing unit and heat exchanger is shown generally at 10 which consists of a series of subunits, each of which has a specific function and which are assembled into a single unit that can, for example, be enclosed in an appropriate size shipping container or an outer vault which is preferably formed of reinforced concrete or steel.

In order to retain heat, the outer surfaces of the unit on all sides are provided with one or more layers of a high-temperature insulation 11. For high temperature applications or for irregularly-shaped components such as valves, pipe joints or the like, similar insulation may be provided.

A steel door 12 as shown in FIG. 2 is provided for access to the heating chamber 13. If desired, an inspection window may be provided in the door.

As noted above, a wide variety of fuel sources may be employed to provide a heat source for the unit. In the preferred embodiment of the invention, natural gas or propane is used as a source of heat which is fed into the heating chamber 13. A burner assembly 14 serves to ignite and burn, the gas or other suitable fuel which may enter the unit via an inlet line 15. Alternatively, ignition may take place outside of the system and the heat may then enter the heating chamber 13.

A forced air blower (not shown) may be used for forced induction into the heating chamber in order to ensure efficient burning of the fuel.

The outer casing of the unit is sealed with the exception of water inlet piping 16, steam outlet piping 17, the fuel inlet 15 or auger feed when a solid fuel is used, and power control wiring conduits. The sealing contributes to the efficiency of the unit to ensure against loss of heat from the unit. The primary function of this outer casing, which includes the water inlet 16 is to be the outermost component of the thermal storage system and as previously noted, several layers of high temperature insulation 18 are required for insertion within the outer casing.

Water enters the unit through the inlet, pipe 16 and flows through the unit as represented by the arrows in the figures. The water is preferably preheated. The diameter of the water-pipe is reduced as seen in FIG. 2 and the water then flows through a series of wall coil sets and mid-wall coils. These coils are preferably formed of high grade copper, stainless steel of other appropriate metals and have an appropriate diameter for the specific application of the system, and are encased in refractory cement 19.

These wall coil sets include the front wall coils 20, top wall coils 21, upper and lower side wall coils 22 and 23, right side wall coils 24, rear wall coils 25, top coils 26, bottom coils 27 and mid-wall coils 28. These coils carry the water which is preferably preheated and which approaches the boiling point which will vary with the pressure.

The coils in each set are formed in a serpentine or “race-track” pattern with the inlets and outlets being coplanar and parallel to each other as seen for example in FIG. 12. This results in a very compact coil set which enables the use of many such coil sets in the unit.

A plurality of vertically oriented steam, tanks 29 which are code design steel pressure vessels. The tanks are designed to withstand the very high pressures and temperatures of the steam contained and stored therein and are placed adjacent to one side of the unit and receive the steam that is generated in additional coil sets which include heating chamber coils 30, horizontal steam generating coils 31, and vertical steam generating coils 32. The steam generating coils are oriented perpendicular to and above the heating chamber 13. The tanks may be insulated if desired although such insulation may not be required since they are located within a chamber where the temperatures may be greater than 150° C.

As water flows from the inlet sequentially through all of the various coil sets, the temperature increases until steam is generated. Thereafter, the steam enters the steam tanks 29. The steam may then, when desired, exit the steam tanks through the steam outlet 17 when it may thereafter serve various purposes. For example, the steam may feed a steam turbine for the generation of electrical power.

As seen in FIG. 2, the heating chamber 13 is located near the lower front of the unit and is heated by a burner assembly 14 such as a PowerFlame®Nova Plus combustion burner manufactured by Power Flame Incorporated, shown in dotted lines. A grate surface may be provided when solid fuels are used and a combustion air inlet may be provided to conduct induction air from a blower if one is used.

It is expected that when forced induction and a refined configuration of heating chamber, temperatures of between 650° C. and 1650° C. can be expected.

By providing coil sets both at the front, rear, top, sides and bottom of the unit as well as adjacent the middle of the unit, a very high efficiency is achieved especially when the water is pre-heated.

As noted above, the water entering the unit via the water inlet 16 passes through all of the wall tube pre-heating coils and then into and through the horizontal heating chamber coils 30 (see FIG. 9) where it is primarily heated and then through vertical and horizontal steam generating coil sets 31 and 32. It will be understood that heated air exiting from the heating chamber 13 will circulate upwardly around and about the various coil sets and the steam generating coils.

A phase change to steam occurs where the heated water reaches saturated steam temperature which varies based upon the water pressure. The steam is saturated at this point.

Steam that exits from the steam generating coils is fed via a manifold 33 directly into the top of the steam tanks 29, four of which are shown in FIG. 3. Obviously, any number of such tanks may be used dependent upon the proposed application of the internally heated steam generation system and heat exchanger. These tanks are provided for storage of steam to allow for fluctuations in steam consumption to balance the steam generation of the system.

When steam is released from the tanks, it passes into an outlet manifold 34 which communicates with the steam outlet 17. The exiting steam may be employed for use in a power plant, steam turbine or any external system where steam may be employed, as for example, generation of electricity, and for providing heat for homes or buildings.

Means are also provided for the removal of exhaust gases from the unit through an exhaust outlet 35. Such gases passing out of the unit will be monitored to determine emission particulate levels and the presence of any unburned hydrocarbons. Monitoring systems of this type are well known in the industry and are commercially available. The monitored data can be used through computer software to adjust the feed of fuel and air induction into the heating chamber to obtain optimum burn performance. 

1. A high efficiency internally heated steam generating system and heat exchanger comprising; A generally rectangular solid shaped outer container; a plurality of capillary serpentine wound tubes arranged as a coil set within and on each of the top, bottom, ends and sides of the container, a heating chamber within the lower portion of said container, means for producing heat in said heating chamber, means to introduce a supply of water into the system, said water being heated in said heating chamber and then passing sequentially through each of the coil sets wherein it changes its phase into steam, at least one vertically oriented steam tank which receives steam from the output of the coil sets, and means to withdraw steam from said at least one steam tank.
 2. The steam generating system and heat exchanger as set forth in claim 1, wherein the water supplied to the system is pre-heated.
 3. The steam generating system and heat exchanger as set forth in claim 1, wherein each of the coil sets include an inlet and an outlet and wherein said inlets and outlets are located in the same plane and are parallel to each other.
 4. The steam generating system and heat exchanger as set forth in claim 3, wherein, each coil set is encased in refractory cement.
 5. The steam generating system and heat exchanger as set forth in claim 1 wherein four steam tanks are provided.
 6. The steam generating system and heat exchanger as set forth in claim 1, wherein, the steam entering the steam tank is superheated.
 7. The steam generating system and heat exchanger as set forth in claim 1, wherein, the steam entering the steam tank is saturated.
 8. The steam generating system and heat exchanger as set forth in claim 1, and further including vertical and horizontal steam generating coil sets in communication with the wall coil sets and being located above the heating chamber.
 9. The steam generating system and heat exchanger as set forth in claim 1, wherein, a grate for holding and burning solid fuel is located within the heating chamber.
 10. The steam generating system and heat exchanger as set forth in claim 3, wherein, gas burner means provides heat into the heating chamber.
 11. The steam generating system and heat exchanger as set forth in claim 3, and further including blower means for providing induction air into the heating chamber.
 12. A high efficiency internally heated steam generating system and heat exchanger comprising; A generally rectangular solid shaped outer container; a plurality of capillary serpentine wound small diameter tubes arranged as a coil set within and on each of the top, bottom, ends and sides of the container, an additional mid-wall coil set located between the ends of the container, a heating chamber within the lower portion of said container, a source of fuel for producing heat in said heating chamber, means to introduce a supply of water into the system, said water being heated in said heating chamber and then passing sequentially through each of the coil sets wherein it changes its phase into steam, at least one vertically oriented steam tank which receives steam from the output of the coil sets, and means to withdraw steam from said at least one steam tank.
 13. The steam generating system and heat exchanger as set forth in claim 12, and further including vertical and horizontal steam generating coil sets in communication with the wall coil sets and the mid-wall coil set and being located above the heating chamber. 14, The steam generating system and heat exchanger as set forth in claim 12, wherein, each coil set is encased in refractory cement. 